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Please help again with these problems: at what compound interest rate per annum must money be invested
if the principal must be tripled in 10 years and interest is calculated quarterly.
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If A is the amount and "r" is the annual compound interest rate, then the future value of the compounded amount is
FV= = .
We want to triple the amount
3A = .
Cancel the factor A in both sides to get
3 = .
Take log base 10 of both sides
log(3) =
Get
= = 0.011928
Hence
= = 1.027846.
It implies
r/4 = 0.027846, r = 4*0.027846 = 0.111384.
ANSWER. The nominal annual compound interest rate should be 11.14%.
Solved.
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What you see in this post, is the STANDARD METHOD solving such problems, shown in all details.
See the lesson
- Problems on discretely compound accounts
in this site, and learn the subject from there.
Also, you have this free of charge online textbook in ALGEBRA-I in this site
- ALGEBRA-I - YOUR ONLINE TEXTBOOK.
The referred lesson is the part of this online textbook under the topic "Logarithms".
Save the link to this online textbook together with its description
Free of charge online textbook in ALGEBRA-I
https://www.algebra.com/algebra/homework/quadratic/lessons/ALGEBRA-I-YOUR-ONLINE-TEXTBOOK.lesson
to your archive and use it when it is needed.
Happy learning (!)
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Regarding your second problem, I do not understand that writing - SO INACCURATELY it is presented.
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